Do the manual cars have a clutch switch stock? I would think it would be necessary for the cruise to know if the drive was dis-engaged. But, I honestly never looked to see if my van had one (and now it's gone). I would assume it was wired into the same input as the P/N switch on the auto cars - if it exsists. If not, then then what happens when you push in the clutch while cruise is on? Not that it's a good idea, but you'd think they'd put a failsafe in...